WPP-owned Wavemaker, which was formed by the merger of MEC and Maxus, has brought Hernandez on board to ensure the global L’Oréal strategy is fully understood and implemented locally by Wavemaker client teams.
Hernandez will be based at the Paris office and report directly to Wavemaker global chief client officer Aaron Smith.
He joins from Mondelez where he has acted as senior director of global media strategy and communications planning since 2012.
Hernandez is credited with increasing global media ROI during his time at Mondelez, particularly across the company’s Oreo, Cadbury and Trident brands.
Smith said: "Client centricity is a key strategic shift for Wavemaker, and with more than 20 years’ experience in media strategy, brand planning, insights and digital transformation across agencies and advertisers, Josep brings all the seniority and expertise we need to deliver for our largest global client.
"He has led some of the most successful marketing cases not only in Cosmetics but also in CPG [Consumer Packaged Goods] with Danone, Nestlé and across other sectors such as technology and finance, for Microsoft and Citibank."
Hernandez joining Wavemaker marks a return to WPP. He spent 15 years within leadership roles at WPP for agencies including Wunderman, Y&R and Ogilvy before leaving in 2012 to go client side.
His time at WPP included stints across the New York, London, Madrid, Barcelona and Los Angeles offices.
Hernandez said: "Having spent the last five years as a client, I have experienced first-hand the challenges advertisers face today.
"The industry requires new agency models that are agile, transparent and scalable, turning data and smart tech into first mover advantages across media, commerce and content strategies.
"Wavemaker’s ambition, its obsession with the purchase journey and its laser sharp focus on client relationships will give the agency and its clients a genuine competitive edge in a highly competitive and constantly changing environment."
Hernandez also serves as chairman of the Euro Effies, which judges marketing communications effectiveness.